Due to rapid development of electronic devices, sales and demands for wearable devices, such as a mobile device, particularly a smart watch, have rapidly increased. As a large capacity battery cannot be mounted in the mobile device, it is necessary to frequently charge the mobile device thereby causing inconvenience to a user. For example, the mobile device needs to be mounted on a cradle whenever being charged.
Further, according to the recent appearance of a smart garment, an issue for a battery capacity and power charging has arisen with respect to the smart garment.
Accordingly, needs for an extension of a charging period and convenient power charging of the mobile device and the smart garment have been increased.